Poster D52, Wednesday, August 21, 2019, 5:15 – 7:00 pm, Restaurant Hall
Early crosslinguistic ERP effects in bilinguals: Automatic parallel access of both L1 and L2 lexicons
Anna Petrova1, Nikolay Novitskiy2,3, Andriy Myachykov1,4, Yury Shtyrov1,5;1Center for Cognition and Decision Making, Higher School of Economics, Russia, 2Department of Linguistics and Modern Languages, The Chinese University of Hong Kong, 3Brain and Mind Institute, The Chinese University of Hong Kong, 4Department of Psychology, Northumbria University, Newcastle-upon-Tyne, 5Center of Functionally Integrative Neuroscience, Institute for Clinical Medicine, Aarhus University
In the modern globalized world many people are multilingual: recent estimates suggest that bilinguals constitute the majority of the world’s population (Bialystok et al, 2012). One of the most debated research questions in the field (for review, see Dunabeitia et al., 2015) is whether two or more languages coexisting in the multilingual mind have separate lexico-semantic storages (Perani et al., 2003; Grosjean, 2014), or a common storage and activation mechanism (Costa et al, 2008; Van Heuven & Dijkstra, 2010; Kroll et al., 2010). This question can be addressed by using a priming task to examine how primes from L1 influence the processing of target words in L2. The present study investigated the crosslinguistic phonological and semantic similarity effects on the bilingual lexicon in late unbalanced bilinguals. Our masked priming paradigm used L1 (Russian) words as masked primes and L2 (English) words as targets. The primes and the targets either overlapped – only phonologically, only semantically, both phonologically and semantically – or did not overlap at all. Participants had to maintain the targets in memory and match them against occasionally presented catch stimuli. Language-related differences in N170 and N400 components were previously reported (Novitskiy et al.. 2019); however, recent investigations into L1 processing suggest that lexico-semantic access commences much earlier, around 30-80 ms (Kimppa et al, 2015, 2016; Shtyrov et al., 2014; Shtyrov and Lenzen 2014), i.e. in the P50 component interval. This raises a question whether the L2 lexical access and interactions between L2 and L1 lexicons may also commence at a much earlier time than previously suggested by studies focused on later components. Our analysis of amplitudes in a 40-60 ms post-stimulus time window demonstrated a marginal main effect of semantics (F=3.62 , p=0.057), as well as a reliable interaction between semantic and phonological overlap (F=21.09, p<0.0001), underpinned, as confirmed by post-hoc analyses, by а specific semantically-driven increase of responses to L2 targets that shared phonological similarity with masked L1 primes. These findings suggest that lexico-semantic co-activation of the two lexicons happens as early as 50 milliseconds after visual word presentation, and a semantic match between prime and target may facilitate the perception of the target. We interpret the increased positive peak as an allocation of resources for processing of a meaningful stimulus, as opposed to mismatched stimuli that do not elicit such an enhancement. The effect of interaction between semantics and phonology is driven by the differences in amplitudes to different semantic conditions, while phonology does not show significant differences in and of itself. This evidence of ultra-rapid cross-linguistic effect in a masked priming task suggests a high degree of automaticity and parallelism in access of both L1 and L2 items. In fact, if a word in a one language can prime the neural processing of a word in another one, this supports the notion of a shared storage with common access. We conclude that the semantic and phonological interplay between L1 and L2 suggest an integrated bilingual lexicon.
Themes: Multilingualism, Reading
Method: Electrophysiology (MEG/EEG/ECOG)